Wire EDM Feed Rate Control for Non-Machining Wire Waste

Solution Overview

Problem

In wire electrical discharge machines, the wire electrode is continuously fed during both machining and non-machining periods, leading to waste and increased motor load, as the processing start and end positions are often distant from the workpiece.

Innovation Solution

Implementing a motor control unit that adjusts the wire electrode feed rate to a lower rate during non-machining periods, only increasing to the set feed rate when the electrode is intersecting the workpiece, thereby reducing unnecessary wire feed and motor load.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the wire electrode is continuously fed at a preset feed rate during both machining and non-machining periods, then the wire electrode is always ready for machining, but the wire electrode is wasted during non-machining periods and the motor load is increased unnecessarily

Engineering Contradiction:

Improvereadiness of wire electrode for machiningVSAvoidwire electrode waste

Core Design Contradiction:

ReliabilityVSLoss of substance

Solution Approach 1:

The patent applies dynamics by making the wire electrode feed rate variable rather than constant. The motor control unit dynamically adjusts the feed rate based on the machining state: using the preset feed rate during machining periods when the wire electrode is intersecting the workpiece, and reducing it to a lower feed rate during non-machining periods when the wire electrode is not intersecting the workpiece. This dynamic adjustment maintains machining readiness while significantly reducing wire electrode waste during idle periods.

Inventive Principle:

Principle #15Dynamics

2Reliability

If the wire electrode is continuously fed at a preset feed rate during both machining and non-machining periods, then the wire electrode is always ready for machining, but the motor load is increased during non-machining periods

Engineering Contradiction:

Improvereadiness of wire electrode for machiningVSAvoidmotor load

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent applies dynamics by making the wire electrode feed rate variable rather than constant. The motor control unit dynamically adjusts the feed rate based on the machining state: using the preset feed rate during machining periods when the wire electrode is intersecting the workpiece, and reducing it to a lower feed rate during non-machining periods when the wire electrode is not intersecting the workpiece. This dynamic adjustment maintains machining readiness while significantly reducing wire electrode waste during idle periods.

Inventive Principle:

Principle #15Dynamics

3Ease of operation

If the processing start and end positions are located away from the workpiece, then the wire electrode can be positioned for machining, but unnecessary wire feed and motor load occur during the positioning periods

Engineering Contradiction:

Improvewire electrode positioningVSAvoidwire electrode waste

Core Design Contradiction:

Ease of operationVSLoss of substance

Solution Approach 1:

The patent applies dynamics by making the wire electrode feed rate variable rather than constant. The motor control unit dynamically adjusts the feed rate based on the machining state: using the preset feed rate during machining periods when the wire electrode is intersecting the workpiece, and reducing it to a lower feed rate during non-machining periods when the wire electrode is not intersecting the workpiece. This dynamic adjustment maintains machining readiness while significantly reducing wire electrode waste during idle periods.

Inventive Principle:

Principle #15Dynamics

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach reduces wire electrode waste and motor load, resulting in more efficient machining by optimizing feed rates based on the electrode's interaction with the workpiece.

Implementation Method 1

generates electrical discharge by applying voltage at an electrode gap between a workpiece and a wire electrode

Methodology Applied

Scientific EffectElectrical discharge: Electric Spark

Data Source

PatentUS11504785B2Wire electrical discharge machine and control method

Publication Date: 2022.11.22 FANUC LTD

AI summary

A wire electrical discharge machine controls a second motor unit including motors for feeding a wire electrode in a wire running direction in which the wire electrode extends, so as to feed the wire electrode at a set feed rate during a machining period from a first time point at which the wire electrode moving relative to a workpiece in a direction intersecting the wire running direction is estimated to enter the workpiece, to a second time point at which the wire electrode is estimated to exit the workpiece. The second motor unit is controlled so as to feed the wire electrode at a feed rate lower than the set feed rate during at least one of a first non-machining period from a processing start time point to the first time point and a second non-machining period from the second time point to a processing end time point.